R. Walton, in Mary Shelley's novel Frankenstein, is Robert Walton. Essentially, Robert Walton is the narrator of the novel. The novel is written as a multiple narrative. That said, while the voice of the novel changes throughout the novel (moving from Walton to Victor to the creature back to Victor and then Walton), many readers forget that Walton is the only true narrative voice of the novel. This said, the novel opens with Walton's letters to his sister (Caroline). He is in search of the seat of magnetism. Giving up all, he has procured a ship and sailors to take him to the North Pole.
Soon into the novel, Letter Four, Walton comes across a half-frozen man on the ice. Pulling him aboard, Walton tries to nurse the man (Victor Frankenstein) back to health. Once able to speak for long periods of time, Victor tells Walton of his life.
As the novel returns to Walton's first-person perspective, Victor warns him of being too ambitious. Victor, allowing his own ambition to lead to his ruin, proves to be the one person who can show Walton the truth about leading a far too ambitious life. Walton, in the end, chooses to end his expedition and head home to England.
Robert Walton, therefore, acts as the opening and closing voice of the novel. He is also the one who is charged with the telling and retelling the story of Victor Frankenstein (much like the mariner in Coleridge's "Rime of the Ancient Mariner"). It is up to Walton to carry on Victor's tale in order to warn all others about the consequences of ambition and the power of nature.
Robert Walton is the sea captain who rescues an almost dead, Victor Frankenstein, in the icy Arctic region, when Victor is chasing the monster, he created. He is Margaret Saville's brother, 28 yrs of age, enthusiastic, and consumed by a fiery ambition to find the shortest route across the globe. He embarks on adventurous mission, as he is obssessed by his quest for knowledge and insight. He is extremely benevolent and patient as he befriends Victor and nurses him to good health. He enjoys company, he is vivacious and humble. In a way, he is Victor's double(alter-ego). Like Victor, Waton is obsessed with his quest. He too leaves his placid domestic life in search of knowledge and achievement, and he too, alternates between offering the selfish explanation of his obsessionand a more altruistic justification.